#自动把图片转成素描

from PIL import Image, ImageFilter, ImageOps  
img = Image.open('E:\\dd\\Python36\\Myproject\\pic\\1.jpg')  
def dodge(a, b, alpha):  
    return min(int(a*255/(256-b*alpha)), 255)  
def draw(img, blur=25, alpha=1.0):  
    img1 = img.convert('L')        #图片转换成灰色  
    img2 = img1.copy()  
    img2 = ImageOps.invert(img2)  
    for i in range(blur):          #模糊度  
        img2 = img2.filter(ImageFilter.BLUR)  
    width, height = img1.size  
    for x in range(width):  
        for y in range(height):  
            a = img1.getpixel((x, y))  
            b = img2.getpixel((x, y))  
            img1.putpixel((x, y), dodge(a, b, alpha))  
    #img1.show()  
    img1.save('E:\\dd\\Python36\\Myproject\\pic\\2.jpg')  
draw(img)  
